Poultry transfer apparatus and method

ABSTRACT

Poultry transported by a first conveyor is hung by the feet from shackles. As the birds are moved horizontally at a constant speed by the first conveyor, they are engaged by transfer shackles of a special construction which are supported from a second conveyor. The transfer shackles include a clamp for each thigh composed of a slot and a retaining lug. When the thighs of each bird are forced into the slots, the retainer lug snaps into place over the open end of the slot to prevent the thigh from being released. The birds are then carried by the transfer shackles to a third conveyor which is also provided with leg shackles. The legs of the bird are brought into registry with the shackles of the third conveyor and a cam assembly engaging the transfer shackle releases the retaining lugs and allows the thighs of the bird to fall from the transfer shackles.

United States Patent Rejsa et al.

[ 5] Feb. 22, 1972 [54] POULTRY TRANSFER APPARATUS PrimaryExaminer--Edward A. Sroka AND METHOD Att0rney-Ronald E. Lund and JamesV. Harmon [72] Inventors: Jack J. Rejsa, Minneapolis, Minn.; Paul K.

Kiker, Ellijay, Ga. [57] ABSTRACT Poultry transported by a firstconveyor is hung by the feet [73] Asslgnee 31 Plusbury Company Mmneapohsfrom shackles. As the birds are moved horizontally at a conm stant speedby the first conveyor, they are engaged by transfer [22] Filed: Oct. 13,1970 shackles of a special construction which are supported from asecond conveyor. The transfer shackles include a clamp for [2]] Appl'each thigh composed of a slot and a retaining lug. When the thighs ofeach bird are forced into the slots, the retainer lug [52] [1.5. Cl...17/11, 198/179 snaps into place over the open end of the S10! (0prevent I118 [51] Int. Cl. ..A22b 3/08 thigh from being released Thebirds aw m carried by the [58] Fldd 01 Search ..198/20, 177, 179, 131;17/11 transfer Shackles to a third conveyor which is also provided withleg shackles. The legs of the bird are brought into registry [56]References Cited with the shackles of the third conveyor and a camassembly UNITED STATES PATENTS engaging the transfer shackle releasesthe retaining lugs and allows the thighs of the bird to fall from thetransfer shackles. 3,548,448 12/1970 Vertegaal ..l7/ll 8 Claims, 7Drawing Figures /32 /307 Ml ya l4 2 9 tux/@4710 um: mam 905 a, Haw90zl60-m- /48 134 J K "I I: I: 1:

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C 3 i -5- /sz $72 C T D Q I54 g l TP/JMFFER I f riu 3' POULTRY TRANSFERAPPARATUS AND METHOD The present invention relates to poultry equipmentand more particularly to a method and apparatus for transferring poultryfrom one conveyor to another and for orienting the birds with respect toone another.

In commercial plants in which poultry is processed on a high volumebasis, conveyors are employed for transferring the poultry from oneoperation to the next. When as in most plants, separate conveyors areemployed for the picking and eviscerating lines, it is necessary totransfer the birds from the picking line conveyor to the evisceratingline conveyor. This was previously done manually. Thus, in a typicalplant operation, birds were removed manually from shackles provided onthe picking line conveyor. In other plants, the birds are cut down bymeans of an automatic hock cutting machine which engages the legs of thebird and severs the legs at the hook joint. The birds then fall onto aconveyor belt, are moved to the evisceration line, and are hung manuallyon the shackles of the evisceration conveyor. Typically the eviscerationline travels at a much slower speed than the picking conveyor andfrequently the birds are positioned in laterally aligned pairs on 6 inchlongitudinally spaced centers with the breasts facing inwardly. Theseprevious systems have been slow and sometimes resulted in a largeaccumulation of birds between the conveyors. In addition the roughoperation has been expensive, unpleasant, and requires a substantialamount of manpower.

In view of these and other deficiencies of the prior art, the inventionhas among its objects the following features and advantages; (a) theability to quickly and efficiently transfer poultry from one conveyor toanother without requirement of hand labor; (b) a provision for engagingand transferring poultry from one conveyor to another without damagingthe meat; (c) a provision for picking up birds that are traveling at arelatively rapid rate; e.g., 50 ft. a minute and transferring them to aconveyor that is traveling at a much slower rate for example 25 ft. perminute; (d) a provision for transferring poultry in two parallel rowsand for orienting the poultry such that the breasts face inwardly; (e) aprovision for coordinating the speed of a transfer conveyor with anevisceration and a picking conveyor; (f) a provision for accuratelyplacing the transfer conveyor shackles in a position adapted to engagethe legs of the birds on the picking conveyor; and (g) a provision forfeeding the transfer conveyor shackles to the picking line only when thebirds are present on the line.

These and other more detailed and specific objects will be apparent inview of the following specifications and drawings wherein:

FIG. I is a schematic showing of the poultry conveyor system.

FIG. la is a partial vertical section through a segment of the transferconveyor and one shackle carriage.

FIG. 2 is a view taken on line 2-2 of FIG. I on a greatly enlargedscale.

FIG. 3 is a horizontal sectional view taken on line 33 of FIG. 2.

FIG. 4 is a side elevational view taken on line 44 of FIG. 1 and FIG. 5is a partial end elevational view taken on line 5-5 of FIG. 4.

FIG. 6 is an enlarged showing of the poultry shackle conveyor.

Briefly, the present invention provides a transferring system forremoving poultry from one conveyor and transferring it to a secondconveyor. The invention also provides a transfer shackle for thispurpose and an assembly for turning the shackle through l80 to orientatethe birds with respect to a vertical axis so that they are facing in theproper direction. A means is provided for feeding the transfer shacklesinto the position in which they will engage a bird only when a bird ispresent on the picking line. A further provision is made for pressingeach bird into engagement with a transfer shackle.

In a preferred embodiment of the invention, birds being conveyed by afirst conveyor are supported therefrom by shackles which engage the feetof the poultry. As the birds progress at a constant speed, they areengaged by transfer shackles of a special construction which aresupported upon a second conveyor. The transfer shackles include clampsadapted to engage each thigh. Birds are forced into the clamps whichinclude open ended slots. Upon becoming engaged in the slots in thetransfer shackles, a spring-loaded retainer lug snaps into place overthe open end of the slot to prevent the thigh from being released. Thebirds are then carried by the transfer shackles to a third conveyorwhich is also provided with leg shackles. The legs of the bird are thenbrought into registry with the shackles of the third conveyor and a camassembly engaging the transfer shackle releases the retaining lugsallowing the legs of the bird to be removed from the transfer shackles.

In the accomplishment of the foregoing and related ends, the inventionthen comprises the features hereinafter fully described and particularlypointed out in the claims, the following description setting forth indetail certain illustrative embodiments of the invention, these beingindicative, however, ofbut a few of the various ways in which theprinciples of the invention may be employed.

Referring now to FIG. I there is shown a picking line conveyor indicatedgenerally by the numeral 10. On the picking line conveyor 10 are aplurality of longitudinally spaced'apart shackles Ila (FIG. 2).Typically the picking line conveyor travels at the rate of 100 birds perminute with the birds being spaced longitudinally on 6 inch centers.This means the conveyor travels at the rate of about 50 feet per minute.The object of the invention is to transfer the birds from the pickingline 10 to an evisceration line conveyor I3 in which the birds travel atthe rate of 100 birds per minute on 6 inch centers and in laterallyaligned pairs. Thus, the evisceration line 13 travels at the rate ofabout 25 feet per minute. It can therefore be seen that if both linesare running at the rate of I00 birds per minute, if the eviscerationline abruptly slows to birds per minute, for example, as required forcleaning or inspection the excess of 20 birds per minute will accumulatewithin a transfer conveyor T in accordance with the invention. Provisionis made for accumulating the birds within the transfer conveyorincluding a gravity storage arrangement which will gravity feed thebirds and provide storage as described below.

As seen in FIG. 1, each bird 11 on picking line 10 in turn strikes limitswitch L52 which is suitably wired to a solenoid 1 provided with a stop12. The stop 12 is operatively associated with transfer conveyor T so asto engage and retain in position a plurality of transfer shackles 20until such time as the solenoid 1 is energized by the contact of one ofthe birds 11 with the limit switch L52. Thus, as seen :in FIG. I, thetransfer shackles 20 feed by gravity from a position roughly indicatedat 21. By inclining the section of the conveyor T downwardly, theconveyor shackles 20 are stored in this manner upstream of the solenoid1 until the limit switch L52 is actuated at which time the retaining lug12 is retracted and shackles 20 are allowed one at a time to transferfrom beyond the solenoid I from right to left as seen in the figures.

Positioned adjacent to the transfer conveyor T downstream from the point21 located laterally therefrom is a shackle elevating rail 22 a portionof which can also be seen in FIG. 2 and 3. The rail 22 as seen in FIG. 1is initially relatively close to the transfer conveyor T and proceedingdownwardly as seen in FIG. I it is located further and further from theconveyor T and is at the same time elevated further from the floorproceeding toward the left in the figure downward. In this way the railengages the surfaces of the transfer conveyor shackles 20 and elevatesthem from the normal vertical free-hanging position to a laterallydisposed position as shown in FIG. 2 and 3 in the area between thesolenoid l and L52. As the transfer conveyor T swings toward the left asseen in FIG. 1 the shackle supporting rail 22 also bends to the left andextends parallel thereto with it. In this manner, the transfer shackles20 are at all times maintained in a horizontal position and are locatedat a precisely controlled elevation which corresponds with the positionof the lower ends of the legs. of the birds 11 on the picking conveyor10 as shown in FIG. 2.

The position and location of the now horizontally oriented transfershackles is controlled by an endless timing chain conveyor 23 (FIGS. 1and la) which is composed of sprockets 24 over which is entrained atiming chain 25 provided with spaced lugs 25a one of which engages eachsuccessive transfer shackle 20. As seen in FIG. la, the lugs 25a projectvertically from the timing chain 25 into a vertically disposed upwardlyopening recess 76 defined by vertically disposed bars 72 and 74 whichfrom a portion of the carriage 52 supporting the transfer shackle 20 onthe rail of the overhead conveyor T. In this way each one of thetransfer shackles 20 is positioned in lateral alignment with one of thebirds 11 on the picking line.

The conveyor 23 is coupled to the picking line by the provision of agearbox 26 connected to a sprocket 25 and driven in turn by a shaft 28that is coupled to caterpillar drive chains 30 and 32 which areentrained respectively over sprockets 300-30 and 32a-32b. As seen inFIG. 1, the center section of the caterpillar chains 30 and 32 engagethe picking line conveyor chain 10 and is therefore driven by it at thesame speed and in the same direction, thereby providing power to shaft28, transmission 26 and sprocket 24 to the timing chain 25.

It can be seen from the above description that as the transfer shackles20 proceed toward the picking line conveyor they will be in anapproximately horizontal position and will be traveling in the samespeed and direction as the birds 11. They will also be positioned in alateral alignment with the birds and their lower or free ends will be inalignment with the joints between the legs and the body.

As shown in FIG. 1, 2, and 3, there is positioned on the opposite sideof the picking line from the transfer shackles 20, a bird positioningbelt 14 comprising an endless belt entrained over a pair of horizontallyspaced-apart idler pulleys l6 and 18 located appropriately so that thedownstream end of the belt assembly 14 is closer to the birds than theupstream end. In this way the birds are engaged by the belt 14 and areforced toward the left. As the birds travel toward the viewer as seen inFIG. 2 they are forced into the transfer shackle 20. The transfershackles themselves are held against movement toward the right by thetrack of the overhead transfer conveyor T. It will be seen that at thispoint the birds are supported both by the shackles 11a of the pickingline conveyor 10 and the transfer shackles 20.

While the birds are supported both by conveyors l1 and transfer conveyorT, they enter the hock cutter 34 which can be of any suitablecommercially available unit such as the equipment known as the HockCutter manufactured by the Gainesville Machine Company of Gainesville,Georgia. This unit includes a pair of cooperating wheels 36 and 38 theformer of which is sharpened on its edge to serve as a cutter which actsagainst a wheel 38 having a circumferentially extending horizontallydisposed groove 38a in which a segment of the blade 36 is engaged. Bothof the wheels 36 and 38 are supported for rotation on vertical axles apair of rolls 39a and 39b engage the legs just before the legs passbetween wheels 36 and 38 to help position the hock joint to be severedby the blade 36. As soon as the hock joint is cut, the birds fall to theapproximate position of FIG. 6. The birds are then supported solely bythe transfer shackle 20.

The transfer conveyor T comprises a rail supported from a series ofvertically disposed hanger rods 40 (FIG. 2) having heads 40a supportingcrossbars 42. Extending longitudinally of the crossbars and projectingdownwardly therefrom are laterally spaced support plates 44 and 46 towhich channels 48 and 50 are secured rigidly as by welding. Between thechannels 48 and 50 are located the carriers 52 which can be formed froman elongated piece of metal provided with suitably bored longitudinallyspaced openings providing support for wheels 54 and axles 56 (FIG. 4).The wheels in turn are engaged upon the lower webs 48a and 50arespectively of the channels 48 and 50. The carrier 52 has a centrallydisposed vertically positioned supporting rod that extends downwardlythrough a bore 16 in carrier 52 of the appropriate size to provide asmooth sliding fit for the rod 58.

As seen in FIG. 2 and 4 a rod 58 is provided with a laterally extendingpin 62 engaged in a V-shaped notch 64 in the upper surface of thecarrier 52. A compression spring 66 is connected between the carrier 52and a crossbar 68 secured rigidly as by welding to the shaft 58. Anorienting pin 70 extends laterally from the crossbar 68 for rotating thetransfer shackle 20 about its vertical axis as will be described below.The lower end of the crossbar 68 is secured to a pair of downwardlyextending parallel links and 82 connected to the crossbar 68 by a pivotpin 83. Fastened to the lower end of the links 80 and 82 by pin 85 is asupport rod 84. A collar 94 which is releasably secured to the rod 84engages the upper end of the compression spring 92. The lower end ofspring 92 is engaged upon a cam follower plate 88 which is bored at 89so slide longitudinally upon the rod 84. Fixed to the lower end of thefollower 88 is a latch that moves as seen in FIG. 4 when the camfollower 88 is forced upwardly against the pressure spring 92 byengagement of the cam rails 90 a and 90b.

The portion of the transfer shackle 20 engaging the thighs of the birdcomprises a plate 102 having parallel spaced-apart legs 103 and 105. Theends of the legs I03I05 are beveled at 104-106 to facilitate insertionof the chicken thighs. Positioned between legs 103 and 105 is a tongueI08 defining open ended slots I09 and 111. The latch members and 112 areprovided with beveled ends which are inclined in the appropriatedirection to facilitate insertion of the thighs. The latch members alsohave retaining lugs 114a, 116a which hold the thighs in place. Thelatches are pivotally connected to the shackle by pivots 118 and 120 andare able to move when the follower 110 is raised by the connectionbetween the follower 110 and tabs 122 and 125 to the dotted linepositions 126 and 128 in FIG. 4 when the follower 88 is engaged by rails90a and 90b thereby releasing the thighs from the shackles.

As described briefly above when the legs of the chicken are carried bythe transfer conveyor T into proximity with the evisceration conveyor 13they are brought into engagement with the shackles 1311 thereof beforethe cam members 900 and 90!; cause the latches 110 and 112 to release.

The passage of the birds from the transfer conveyor T to theevisceration line 13 will now be described.

As shown in FIG. 1, the evisceration line conveyor travels toward thetransfer conveyor initially from right to left as seen in the figure,thence over wheel 132, wheel 134 and from left to right between parallelhorizontally disposed laterally spaced sections T1 and T2 of thetransfer conveyor T composed of identical rails T as described hereinabove. The transfer conveyor section T1 and T2 are positioned at aslighter lower elevation than the conveyor evisceration line 13 at theleft in the figure. However, in the section designated 135 the lines 13and 15 are inclined downwardly proceeding from left to right therebycausing the hock joints to slide downwardly to the hooks and to theshackles 13a as shown in FIG. 5. As soon as this has been done, theshackles are opened by engagement of the cam follower 88 with the camrails 90a and 90b.

The drive system for coordinating the transfer of birds from thetransfer conveyor T to the evisceration line 13 comprises a gearbox 136connected to wheel 132 which is coupled by means of the drive shaft 138right-angle gearbox 140, shaft 141 to a tractor drive 142 comprising apair of laterally spaced drive chains 144 and 146 each from the shaft141 and positioned in vertical alignment with the portions T1 and T2 ofthe conveyor T. The chains 144 and 146 are provided with lugs (notshown) identical to the lugs 25a of chain 25 which engage the recess 76of the carriages 52 in the same manner and thereby locate the transfershackles in lateral alignment with the shackles 13a of the eviscerationline conveyor 13.

Locating the birds in laterally aligned pairs on conveyor 13 isaccomplished by the division of the transfer conveyor T into two partsT1 T2. Separation of the birds 11 into the sections T1 and T2 isaccomplished by a cylinder 149 (FIG. I) which is connected to swing asegment 150 to the left or right about pivot 52 so that its free end isin alignment with either of track sections T1 and T2 so that eachconsecutive bird is fed alternately to track sections T1 and T2. As canbe seen in FIG. 1, the breasts of the birds 11 after leaving the hockcutter all face toward the right. The shackles in section T1 are pivotedthrough 180 about a vertical axis by stationary lug 153 which strikesthe pin 70 and a lug 154 which strikes the crossbar 68 thereby drivingthe retaining pin 62 out of the notch 64 as the shackle is turnedthrough 180. The breasts of the birds then face outward away from theevisceration line conveyor 13.

As the shackles travel the descending portion of the conveyor 135, thefree ends of the legs (the hocks) will slide into the shackles 13a andit is just after this has been completed that the follower 88 engagesthe cam tracks 90a and 90b. The cams then elevate the follower 88 andthereby elevate tabs 122 and 124. The retaining lugs are then moved tothe retracted positions 126 and 128. The birds then fall out of theshackles 20 and are supported solely by the shackles of the conveyor 13.

The control system for advancing the birds on conveyor T will now bedescribed. Normally, the carriages supporting the transfer shackle 20are carried by gravity into the timing chain 25. L52 is normally closed.If L52 is opened by the passage of a bird then current is not suppliedto the solenoid 1 whereupon the solenoid lever 12 rises and allows acarriage and shackle to feed into the timing chain 25. L51 allows acarriage and shackle to feed into the timing chain 25. L51 senseswhether or not there are transfer shackles present in storage. lfthereare not, the picking line conveyor 10 is halted through suitableelectrical connections to the drive of the picking line conveyor 10 (notshown).

The limit switches L53 and L54 are wired to solenoids 2 and 3respectively and are normally closed switches. If a bird contacts aswitch it opens, in which case the solenoids 2 or 3 as the case may beis actuated whereupon the solenoid armature drops down into the conveyorracks halting the forward movement of the carriages therein therebypreventing them from entering the timing chains of the tractor drive142. In this way, the feed to the tractor drive 142 is stopped when nobirds are present in sections T1 and T2. The empty transfer shackles insection T1 are rotated back to their original position by stationaryposts 160 and 162.

We claim:

1. A method fro transferring poultry from a first conveyor to a secondconveyor comprising; providing a transfer shackle including a grippingmeans for engaging and retaining a portion of the body of the bird,bringing the transfer shackle into proximity with a bird supported uponthe first conveyor, engaging the bird upon the transfer shackle,disengaging the bird from the first conveyor whereby it is supportedsolely by the transfer shackle conveyor, locating the birds on thetransfer shackle with respect to the shackles on the second conveyor,engaging portions of the birds with shackles of the second con veyor anddisengaging and removing the transfer shackle from the bird.

2. The method of claim 1 wherein the transfer shackle is placed inproximity with the joint between a leg and the body and is engagedthereupon.

3. The method of claim 1 wherein the transfer shackle is provided with amember having an open-ended recess and a leg of the bird is engagedtherewith by forcing the leg into the open ended recess in the shackle.

4. A transfer apparatus for carrying poultry from a first conveyor to asecond conveyor comprising; an endless transfer conveyor, a plurality oftransfer shackles on the transfer conveyor, clamp means on the transfershackles for engaging and retaining portions of the body of the bird,said transfer conveyor having a means for advancing the shacklestherealong, means for locating the transfer shackle with respect tobirds on the first conveyor, means for placing the transfer shackle intoengagement with the birds, means for releasing the birds from the firstconveyor, means for engaging parts of the birds on the transfer conveyorwith the second conveyor, and means operative upon the transfer shacklesfor disengaging the birds therefrom when engaged by the second conveyor.

. The apparatus of claim 4 wherein the transfer shackles are freely andindependently movable back and forth on the transfer conveyor and atiming means including an endless timing number having lugs thereonadapted to engage the shackles is operative connected to the firstconveyor for locating the transfer shackles with respect to the birdslocated on the first conveyor whereby the transfer shackles arcpositioned in alignment with the birds on the first conveyor.

6. The apparatus according to claim 4 wherein a sensing means isoperatively associated with the first conveyor for sensing whether ornot birds are present thereon and a movable stop member positioned formovement toward and away from the shackles on the transfer conveyor isconnected to the sensing means in the sense such that the stop will bemoved to a position obstructing the forward movement of the transfershackle when the sensing means is not actuated by the presence ofa birdon the first conveyor.

7. The apparatus of claim 4 wherein the transfer shackles comprisesupporting means extending downwardly from the transfer conveyor and ashackle member at the lower end thereof having at least one open-endedslot therein to receive a portion of the body of the bird and aretaining lug means operatively associated with the open end of the slotto close the open end of the slot after the said body portion has beenforced into the slot and a means operatively associated with the lug formoving the lug to an out-of-the-way releasing position when the bird isto be withdrawn from the shackle.

8. The apparatus of claim 4 wherein the transfer conveyor is dividedinto two similar parallel laterally spaced sections positioned in parton opposite sides of the second conveyor and means is provided on thetransfer conveyor for orienting the birds thereon such that the birds onboth sides of the second conveyor face the second conveyor.

1. A method fro transferring poultry from a first conveyor to a secondconveyor comprising; providing a transfer shackle including a grippingmeans for engaging and retaining a portion of the body of the bird,bringing the transfer shackle into proximity with a bird supported uponthe first conveyor, engaging the bird upon the transfer shackle,disengaging the bird from the first conveyor whereby it is supportedsolely by the transfer shackle conveyor, locating the birds on thetransfer shackle with respect to the shackles on the second conveyor,engaging portions of the birds with shackles of the second conveyor anddisengaging and removing the transfer shackle from the bird.
 2. Themethod of claim 1 wherein the transfer shackle is placed in proximitywith the joint between a leg and the body and is engaged thereupon. 3.The method of claim 1 wherein the transfer shackle is provided with amember having an open-ended recess and a leg of the bird is engagedtherewith by forcing the leg into the open ended recess in the shackle.4. A transfer apparatus for carrying poultry from a first conveyor to asecond conveyor comprising; an endless transfer conveyor, a plurality oftransfer shackles on the transfer conveyor, clamp means on the transfershackles for engaging and retaining portions of the body of the bird,said transfer conveyor having a means for advancing the shacklestherealong, means for locating the transfer shackle with respect tobirds on the first conveyor, means for placing the transfer shackle intoengagement with the birds, means for releasing the birds from the firstconveyor, means for engaging parts of the birds on the transfer conveyorwith the second conveyor, and means operative upon the transfer shacklesfor disengaging the birds therefrom when engaged by the second conveyor.5. The apparatus of claim 4 wherein the transfer shackles are freely andindependently movable back and forth on the transfer conveyor and atiming means including an endless timing number having lugs thereonadapted to engage the shackles is operative connected to the firstconveyor for locating the transfer shackles with respect to the birdslocated on the first conveyor whereby the transfer shackles arepositioned in alignment with the birds on the first conveyor.
 6. Theapparatus according to claim 4 wherein a sensing means is operativelyassociated with the first conveyor for sensing whether or not birds arepresent thereon and a movable stop member positioned for movement towardand away from the shackles on the transfer conveyor is connected to thesensing means in the sense such that tHe stop will be moved to aposition obstructing the forward movement of the transfer shackle whenthe sensing means is not actuated by the presence of a bird on the firstconveyor.
 7. The apparatus of claim 4 wherein the transfer shacklescomprise supporting means extending downwardly from the transferconveyor and a shackle member at the lower end thereof having at leastone open-ended slot therein to receive a portion of the body of the birdand a retaining lug means operatively associated with the open end ofthe slot to close the open end of the slot after the said body portionhas been forced into the slot and a means operatively associated withthe lug for moving the lug to an out-of-the-way releasing position whenthe bird is to be withdrawn from the shackle.
 8. The apparatus of claim4 wherein the transfer conveyor is divided into two similar parallellaterally spaced sections positioned in part on opposite sides of thesecond conveyor and means is provided on the transfer conveyor fororienting the birds thereon such that the birds on both sides of thesecond conveyor face the second conveyor.